Borrowings - Long-Term Debt, Debt Issued (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Jun. 30, 2019
Long-term Debt Instrument
Notes Issued
Aggregate amount of debt issued		$ 20,000
Euro fixed-rate notes
Notes Issued
Aggregate amount of debt issued	$ 4,100	$ 5,700
Fixed rate debt due in 2021
Notes Issued
Outstanding debt redeemed	$ 2,900
Aggregate principal redeemed (as a percent)	100.00%
Loss upon redemption on notes	$ (49)

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=117329964&loc=d3e12355-112629

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=117329964&loc=d3e12317-112629

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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Balance Type:	credit
Period Type:	duration